Glossary of Power Engineering Terms
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| Term | Definition |
|---|---|
| NATURAL DRAFT |
Where no mechanical means is used to provide air for combustion. Airflow into the combustion chamber is the result of warm air being less dense than cool air. |
| NATURAL GAS |
A gaseous fuel comprised mainly of methane; it is found beneath the earth's surface. |
| NATURAL MAGNET |
A naturally occurring mineral (Fe3O4) that has magnetic properties such as the ability to attract other magnetic materials and is affected by the earth's magnetic field |
| NEGATIVE VALENCE |
Having a negative charge. Group V, VI, and VII elements on the periodic table form negative ions and tend to accept electrons. |
| NET POSITIVE SUCTION HEAD (NPSH) |
The amount of pressure that is required on the suction side of the pump to prevent cavitation. |
| NETWORK |
In computing, two or more computers connected for the purposed of exchanging messages and sharing data and system resources. |
| NEUTRALIZATION |
Addition of an acid or alkali (base) to a liquid to cause the ph of the liquid to move towards a neutral pH of 7.0. |
| NEUTRON |
A subatomic particle that has a mass almost equal to the proton but with no electronic charge, located in the nucleus of the atom. |
| NFPA |
National Fire Protection Association. |
| NODE |
A terminal in a computer network. |
| NON-FERROUS |
Metal that does not contain iron. |
| NON-RETURN VALVE |
A check valve that can be manually closed to prevent the back flow of steam from a header to a boiler. |
| NONCONDENSABLE GAS |
Gas in a system that does not condense at the temperature and pressure at which it exists in the system. |
| NORMAL |
In mechanics, perpendicular or at a right angle (90 degrees) to something. A normal stress is produced in a plane at 90 degrees to the force that is producing it. |
| NOUN |
A word that names a person, place, object, event, idea, or activity. |
| NUCLEAR FISSION |
The splitting of the atom or nucleus of the atom into subatomic particles resulting in the release of radiation and heat. |
| NUCLEAR WASTE |
The by-product or waste from nuclear fission reactions. |
| NUCLEUS |
The dense central core of the atom consisting of protons and neutrons. |
| NUMERATOR |
The number above the line in a common fraction; the numerator is divided by the denominator. If four is divided by seven (4/7), then 4 is the numerator. |